The SLF SnowPro-40 is using the same dimensions and structure as the probes originally designed and studied by A. Denoth [1]. He obtained relations between permittivity 𝜖  and snow density 𝜌 and liquid water content LWC that are well accepted in the researcher community. For snow profiles which are clearly below 0°C the density of dry snow ρdry is calculated using the following empirical formula (Denoth, 1989 [1]):